System and method for testing sensitivity of energetic material from milligram level to sub-milligram level

Abstract

The invention discloses a system and a method for testing sensitivity of energetic materials from milligram level to sub-milligram level, and belongs to the field of material testing. Aiming at the problems of high sample consumption and high result error rate of the existing energetic material test, the invention provides a sensitivity test system for a milligram-grade to sub-milligram-grade energetic material, which comprises a pressure loading module for applying dynamic pressure to an energetic sample, collecting light with at least two different wavelengths, and determining the sensitivity of the energetic material. The public light path module is used for receiving light paths with different wavelengths and separating the light paths with different wavelengths to different functional components in the functional component module; the functional component module is used for in-situ observation of structural evolution and reaction phenomena of an energetic sample under pressure loading; and the synchronous control module is used for ensuring time synchronism when the pressure loading module, the public light path module and the functional component module work. According to the method, accurate measurement of the sensitivity of the energetic material in milligram and even sub-milligram levels is realized, the test result is objective, the repeatability is high, and a powerful means is provided for rapid safety evaluation and detonation mechanism research of the novel energetic material.

Description

Technical Field

[0001] This invention belongs to the field of testing technology for the safety performance of energetic materials, and more specifically, relates to a sensitivity testing system and method for energetic materials at the milligram to sub-milligram levels. Background Technology

[0002] The mechanical sensitivity, especially impact sensitivity, of energetic materials (such as explosives and propellants) is a core parameter for assessing their safety during production, transportation, storage, and use. Traditional sensitivity testing methods, such as drop hammer impact tests, typically require tens of milligrams of sample, and the test results are mostly qualitative or semi-quantitative binary judgments (i.e., "ignition" or "non-ignition"), making it difficult to accurately quantify the material's sensitivity threshold. Furthermore, traditional methods cannot observe the microstructural evolution and initial chemical reaction processes of materials under impact loads in situ, severely limiting in-depth research into initiation mechanisms. With the advancement of research and development of novel energetic materials (such as nano-energetic materials and energetic eutectics), the amount of sample obtainable in the early stages of material synthesis and screening is often extremely limited (below milligrams). Traditional testing methods, due to inherent bottlenecks such as large sample consumption, low testing accuracy, and lack of process visualization, can no longer meet the needs of modern energetic material research and development. Therefore, developing a new sensitivity measurement technology capable of achieving micro-dose, high precision, quantification, and process observation capabilities has become a key technical problem urgently needing to be solved in this field.

[0003] For example, Chinese patent application CN202111532131.0, published on April 5, 2022, discloses a physical property characterization system and method based on dynamic loading, including: a dynamic loading device, a signal generating device, and a physical property characterization device connected in sequence; the dynamic loading device is used to dynamically drive and rapidly realize the pressure change of the sample to be tested in a diamond anvil cell; the signal generating device is used to generate the voltage signal and synchronously transmit it to the dynamic loading device and the physical property characterization device, so that the physical property characterization and dynamic loading are realized synchronously; the physical property characterization device is used to display the physical property characterization of the sample to be tested under pressure change based on the synchronous signal, and the physical property characterization is realized synchronously with dynamic loading; the time scale range of the physical property characterization device is from seconds to microseconds. The shortcomings of this patent are: the general module cannot meet the problems of sensitivity quantification and in-situ observation of small doses of energetic materials, and the detection accuracy is generally poor.

[0004] For example, Chinese patent application CN202311037400.5, published on October 17, 2023, discloses an impact performance testing system and method based on a Hopkinson bar. The impact performance testing system includes a pulsed laser, a spatial filter, a lens, a beam splitter, a reflector, a sample, a holographic imaging camera array module, an illumination system, a high-speed imaging camera array module, and a Hopkinson bar, connected sequentially. The method involves the sample deforming, breaking, igniting, and generating a debris cloud after impact with the Hopkinson bar; the holographic imaging camera array module captures the shock wave and debris cloud information of the sample's reaction process; and the high-speed imaging camera array module captures the macroscopic data information of the sample's reaction process. The limitation of this patent is that applying Hopkinson bar technology to micro-samples presents classic measurement challenges. Summary of the Invention

[0005] 1. The problem to be solved To address the problems of high sample consumption and high error rate in existing energetic material testing methods, this invention provides a sensitivity testing system and method for milligram- to sub-milligram-level energetic materials. This invention successfully achieves accurate and quantitative measurement of the sensitivity of milligram- and sub-milligram-level energetic materials, and simultaneously visualizes their dynamic response process. Furthermore, the test results are objective and highly repeatable, completely overcoming the limitations of traditional methods that rely on large quantities of explosives, subjective judgment, and superficial observation. This provides a powerful technical means for the rapid safety assessment and detonation mechanism research of novel energetic materials.

[0006] 2. Technical Solution To solve the above problems, the present invention adopts the following technical solution.

[0007] A sensitivity testing system for milligram- to sub-milligram-level energetic materials includes: Pressure loading module: used to apply dynamic pressure to energetic samples; Common optical path module: used to collect light of at least two different wavelengths and separate the optical paths of different wavelengths into different functional components in the functional component module; Functional component module: used for in-situ observation of the structural evolution and reaction phenomena of energetic samples under pressure loading; Synchronization control module: Used to ensure the time synchronization of the pressure loading module, common optical path module and functional component module when they are working.

[0008] Furthermore, the pressure loading module includes a diamond anvil cell for placing an energetic sample, a brake for dynamically loading and unloading pressure on the diamond anvil cell during operation, and a pre-tightening component for initial alignment and static pre-tightening of the diamond anvil cell before operation; and the brake is electrically connected to a power amplifier, which is electrically connected to a function generator.

[0009] Furthermore, it also includes a support, on which a diamond anvil is provided, and a brake is threadedly connected to the bottom of the support; and the brake is a piezoelectric ceramic actuator with a ring structure.

[0010] Furthermore, the common optical path module includes a first-stage multicolor beam splitter, a second-stage multicolor beam splitter, a third-stage multicolor beam splitter, and an objective lens arranged sequentially along the same optical axis, with the objective lens located close to the pressure loading module; The first-stage polychromatic beam splitter, the second-stage polychromatic beam splitter, and the third-stage polychromatic beam splitter each correspond to different wavelengths of light. Meanwhile, the first-stage multicolor beam splitter, the second-stage multicolor beam splitter, and the third-stage multicolor beam splitter each separate the corresponding optical path into different functional components in the functional component module.

[0011] Furthermore, the first-stage multicolor beam splitter is highly reflective of mid-infrared light, the second-stage multicolor beam splitter is highly reflective of visible light, and the third-stage multicolor beam splitter is highly reflective of specific laser wavelengths. Furthermore, the reflecting surfaces of the first-stage multicolor beam splitter, the second-stage multicolor beam splitter, and the third-stage multicolor beam splitter are all at a 45° angle to the same optical axis, and the center of the same optical axis is coaxially and cofocally set with the center of the sample cavity of the diamond anvil cell. The focusing center of the objective lens is aligned with the center of the sample chamber of the diamond anvil cell.

[0012] Furthermore, the functional component module includes an infrared spectroscopy measurement component, a Raman spectroscopy measurement component, a fluorescence spectroscopy measurement component, and a high-speed imaging component; The infrared spectroscopy measurement component emits infrared light to transmit and excite the energetic sample. The transmitted signal is collected by the objective lens and transmitted to the first-stage multicolor beam splitter, which then reflects the signal to the infrared detector in the infrared spectroscopy measurement component. The Raman spectroscopy measurement component emits a laser beam, which is reflected by the third-stage multicolor beam splitter and enters the common optical path. The laser beam is then focused by the objective lens to excite the sample. The generated Raman scattered light returns along the original path and passes through the first-stage multicolor beam splitter, the second-stage multicolor beam splitter, and the third-stage multicolor beam splitter in sequence. After being reflected by the Raman / fluorescence beam splitter, it is sent to the Raman spectroscopy detector in the Raman spectroscopy measurement component. The fluorescence spectroscopy measurement component emits a laser, and the resulting fluorescence signal returns along the original path, passing sequentially through the first-stage multicolor beam splitter, the second-stage multicolor beam splitter, and the third-stage multicolor beam splitter, before being reflected by the Raman / fluorescence beam splitter to the fluorescence detector in the fluorescence spectroscopy measurement component; wherein the fluorescence spectroscopy measurement component and the Raman spectroscopy measurement component share the same laser source. The high-speed imaging component is located on the reflected light path side of the second-stage multicolor beam splitter, directly acquiring the morphology and emission images of energetic samples during the pressure loading process. After being reflected by the second-stage multicolor beam splitter, the images are received by the high-speed camera in the high-speed imaging component.

[0013] Furthermore, the infrared spectral measurement component includes an infrared light source, a filtering unit, and an infrared detector; and the infrared light source is located on the transmission optical path side of the first-stage multicolor beam splitter. The Raman spectroscopy measurement assembly includes a pulsed laser, a Raman / fluorescence beam splitter, a Raman filter, and a spectral detector; and the pulsed laser is positioned on the reflected light path side of the third-stage multicolor beam splitter. The fluorescence spectroscopy measurement component includes a pulsed laser, a Raman / fluorescence beam splitter, a fluorescence filter, and a fluorescence detector; wherein the Raman spectroscopy measurement component and the fluorescence spectroscopy measurement component share the same pulsed laser and Raman / fluorescence beam splitter. The high-speed imaging component includes a filter and a high-speed camera, both of which are located on the reflected light path side of the second-stage multicolor beam splitter.

[0014] Furthermore, the synchronization control module includes a timing controller and a multi-channel shielded cable. The multi-channel shielded cable sends timed trigger and clock signals to components in the pressure loading module, common optical path module, and functional component module to ensure the time synchronization of all actions and data acquisition.

[0015] A method for using a sensitivity testing system for milligram- to sub-milligram-level energetic materials as described in any of the above technical solutions, comprising the following steps: S1: The energetic sample to be tested and the ruby ​​pressure gauge are loaded together in the sealed sample chamber of the pressure loading module; S2: The synchronous control module triggers the pressure loading module to apply controllable pressure to the sample; at the same time, the synchronous control module triggers the functional component module to collect pressure signals, molecular structure signals and morphology image signals in real time during the pressure loading process. S3: Based on the acquired synchronous pressure signal, molecular structure signal, and morphology image signal, analyze and determine the sensitivity parameters of the energetic sample.

[0016] Furthermore, step S3 specifically includes: By fitting the displacement of the ruby ​​fluorescence peak, the pressure change curve in the sample chamber over time is inverted and recorded in real time to determine the pressure amplitude and loading rate of dynamic loading. By analyzing the changes in characteristic peaks of the infrared absorption spectrum and Raman spectrum of the sample during the dynamic process, the starting point and extent of chemical decomposition of energetic samples can be determined. By analyzing the sample morphology, color, or luminescence abrupt changes recorded by high-speed imaging, evidence can be obtained of the occurrence of chemical reactions. Using the synchronization timestamp, the critical pressure value P that triggers sample decomposition was determined. R and its corresponding instantaneous loading rate V; Using the formula S=P R The dynamic sensitivity factor S under this dynamic loading condition is calculated as a key indicator for quantitatively evaluating the impact sensitivity of energetic materials.

[0017] 3. Beneficial effects (1) The present invention achieves dynamic and controllable loading of small-dose samples through a pressure loading module; the common optical path module efficiently separates the mixed light emitted by the sample according to different wavelengths, so that the same tiny sample can generate multiple signals that can be used to analyze temperature field, molecular structure and morphological changes during one loading process, thereby maximizing information; the functional component module can simultaneously observe the physical fragmentation process and the chemical reaction initiation time of the sample with only milligram-level samples, thereby achieving multi-dimensional in-situ diagnosis; the synchronous control module accurately synchronizes pressure loading, multispectral excitation and signal acquisition during the dynamic loading process at the microsecond or even nanosecond level. The precise timing control makes the conditions of each small-dose experiment highly consistent, greatly improving the repeatability of the test results and making sensitivity analysis based on small sample statistics possible; the whole system successfully realizes accurate and quantitative measurement of the sensitivity of milligram-level and even sub-milligram-level energetic materials, and simultaneously visualizes its dynamic response process; at the same time, the test results are objective and highly repeatable, completely changing the limitations of traditional methods that rely on large doses, subjective judgment and superficial observation, and providing a powerful technical means for the rapid safety assessment and detonation mechanism research of new energetic materials; (2) The pressure loading module of the present invention uses a diamond anvil to support a small sample, so that only a sample amount in the microgram range is needed to complete the simulation of the entire process from elastic deformation to impact breakage; at the same time, the annular hollow structure of the actuator allows the light source to penetrate the hollow cavity of the piezoelectric ceramic from bottom to top and directly irradiate the sample on the diamond anvil, avoiding the problem of the actuator blocking the light path and ensuring the accuracy of signal acquisition; the setting of the pre-tightening component can precisely adjust the parallelism and initial contact force of the diamond anvil before the experiment, ensuring that the upper and lower anvil surfaces are in contact with the micro sample, avoiding premature breakage or uneven force due to poor initial contact, and ensuring uniform pressure application of small sample doses; the pressure loading module can support programmable waveform loading, and can systematically study the sensitivity characteristics under different loading rates, adapting to the testing needs of micro samples of new energetic materials; (3) The common optical path module of the present invention designs the common optical axis of the three-stage beam splitter and the center of the sample cavity of the diamond anvil cell as coaxial and confocal, and ensures that the focusing center of the objective lens coincides with it, so that the excitation point and the signal acquisition point are strictly determined in the same small area of ​​the sample regardless of the wavelength of light used; ensures that during dynamic loading, the spectral signal always originates from the key position on the sample where deformation or reaction is taking place, providing a solid spatial consistency basis for subsequent data correlation; at the same time, the sequentially arranged multicolor beam splitter achieves the purpose of step-by-step beam splitting, avoiding the signal loss caused by using movable lens groups or time-division switching, and realizing the synchronous and interference-free acquisition of all spectral information in a dynamic event; the focusing center of the objective lens is aligned with the center of the sample cavity of the diamond anvil cell, ensuring that the excitation light energy is focused on the micro sample to the maximum extent, and the response signal of the sample can be collected by the objective lens to the maximum extent and sent back to the common optical path, ensuring transmission efficiency; (4) The functional component modules of the present invention observe molecular bond changes through infrared spectroscopy measurement components, observe crystal structure through Raman spectroscopy measurement components, use fluorescence spectroscopy measurement components for pressure calibration, and observe macroscopic reactions through high-speed imaging components, covering the full-dimensional diagnostic capabilities of chemistry, physics and macroscopicity; the infrared light source and the ring piezoelectric ceramic actuator are set coaxially to realize transmission detection, and Raman and fluorescence share the same optical path to form a three-dimensional detection system of "chemistry-physics-macroscopic", which changes the limitation of traditional sensitivity testing that can only rely on a single appearance for judgment; the synchronization control module adopts the closed-loop logic of "unified triggering-time sequence scheduling-delay compensation-time stamp binding", and the synchronization accuracy reaches the microsecond level, which can accurately associate the pressure loading and reaction start time, providing core support for subsequent data and solving the defects of insufficient synchronization accuracy and ineffective data association; (5) The method of the present invention achieves accurate quantification of sensitivity by loading samples, dynamic loading, simultaneous acquisition of multiple signals, data analysis, and calculating the dynamic sensitivity factor by multiplying the critical pressure and loading rate. It solves the problems of large sample requirements, qualitative results, and inability to observe in situ in traditional sensitivity testing methods, and provides an effective means for safety assessment and mechanism research of trace energetic materials. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the system structure of the present invention; Figure 2 This is a schematic diagram of the method flow of the present invention; Figure 3 This is a schematic diagram of the infrared and Raman spectra during the dynamic loading of a small dose of CL-20; Figure 4 These are high-speed photographs of a small-dose CL-20 explosion captured during dynamic loading. Figure label: 101. Support; 102. Diamond anvil; 103. Piezoelectric ceramic actuator; 104. Power amplifier; 105. Function generator; 201. First-order polychromatic beam splitter; 202. Second-order polychromatic beam splitter; 203. Third-order polychromatic beam splitter; 204. Objective lens; 301. Infrared light source; 302. Filtering unit; 303. Infrared detector; 401. Optical filter; 402. High-speed camera; 501. Pulsed laser; 502. Raman / fluorescence beam splitter; 503. Raman filter; 504. Raman spectroscopy detector; 601. Fluorescent filter; 602. Fluorescent detector; 7. Synchronization control module. Detailed Implementation

[0019] The present invention will now be further described with reference to specific embodiments and accompanying drawings.

[0020] like Figure 1 As shown, a sensitivity testing system for milligram- to sub-milligram-level energetic materials includes: Pressure loading module: Used to apply dynamic pressure to energetic samples; the mass of the energetic sample is ≤1mg. The pressure loading module performs precise simulation: For energetic samples ranging from milligram to sub-milligram, it uses precision loading methods such as piezoelectric actuators to accurately control the amplitude, pulse width, and loading rate of the dynamic pressure, avoiding the test deviation caused by uneven stress state under large drug doses in the traditional drop hammer method; at the same time, only microgram-level sample amounts are needed to complete the simulation of the entire process from elastic deformation to impact breakage, fundamentally solving the safety risks and material waste caused by the reliance on gram-level drug doses in traditional sensitivity testing; Common optical path module: Used to collect light of at least two different wavelengths and separate the optical paths of different wavelengths into different functional components in the functional component module; the common optical path module collects signals, and the at least two different wavelengths of light exist in a coaxial common optical path, focusing laser excitation and signal collection on the same sample point, which greatly improves the collection efficiency of micro-samples and ensures the signal-to-noise ratio; at the same time, the common optical path can realize the efficient separation of mixed light emitted by the sample according to wavelength, so that the same micro sample can simultaneously generate multiple signals that can be used to analyze temperature field, molecular structure, and morphological changes during a single loading process, maximizing information with minimal usage; Functional component module: used for in-situ observation of the structural evolution and reaction phenomena of energetic samples under pressure loading; the functional component module performs multi-dimensional in-situ diagnosis; this functional component module can integrate infrared spectroscopy (measure temperature / hot spots), Raman spectroscopy (measure molecular structure / decomposition products), fluorescence spectroscopy (measure pressure / electronic state) and high-speed imaging (measure morphology / luminescence), using only milligram-level samples, to simultaneously observe its physical fragmentation process and the onset time of chemical reaction, achieving comprehensive diagnosis with minimal usage; Synchronization Control Module 7: This module ensures the time synchronization of the pressure loading module, common optical path module, and functional component modules during operation. Synchronization Control Module 7 guarantees time consistency; precise timing control ensures highly consistent conditions for each small-dose experiment, significantly improving the repeatability of test results.

[0021] The applicant wishes to clarify that this application primarily targets energetic materials at extremely low doses. Small-dose samples (e.g., below milligram levels) struggle to form a stable impact-bearing surface, leading to uneven impact energy transfer and extremely poor repeatability of test results—a major pain point for the entire industry. Currently, there are three main methods for measuring the sensitivity of energetic materials at doses below milligram: laser micro-explosion spectroscopy, improved traditional testing methods for submicron / nanomaterials, and small-scale impact sensitivity testing. Among these, the "laser micro-explosion" technology developed by the Beijing Institute of Technology team is currently the most cutting-edge solution capable of handling minute quantities. Its advantages include extremely small sample sizes, high safety, predictability of multiple parameters, and high efficiency. However, as a novel method, it requires complex predictive models and demands highly specialized equipment and data interpretation skills. The reliability of improved traditional testing and small-scale impact sensitivity testing methods is questionable, with results deviating significantly from theoretical values.

[0022] Based on this, the applicant has continuously researched and explored, and proposed the technical solution of this application. This application achieves the reduction of the required amount of explosive to be tested from the gram level to the milligram level or even the sub-milligram level through the synergistic effect of four modules, which greatly reduces the amount of sample consumed and also reduces the experimental risk to a certain extent. At the same time, it integrates in-situ diagnosis of physical, chemical and thermal dimensions on extremely small samples, ensuring the accuracy of testing on the basis of small doses, and providing technical means that traditional large-dose testing cannot achieve for the initial safety screening of new energetic materials and in-depth research on the detonation mechanism.

[0023] Furthermore, the modules in this embodiment are not simply an aggregation of modules; rather, they achieve their prominent substantive features and significant progress through the synergistic interaction between them, as detailed below: This application does not simply involve physically stacking functional components. Instead, based on the entire process requirements of sensitivity measurement of energetic materials under dynamic pressure loading, it achieves deep integration between components through common optical path coupling and synchronous control timing scheduling. This breaks through the functional limitations of individual components and produces a significant synergistic effect of 1+1>2. Specifically, this is reflected in: 1. Spatiotemporal synchronization of multi-dimensional signals enables precise sensitivity determination. The detection signals of each component are bound to a unified timestamp through the synchronization control module 7, accurately linking pressure evolution, molecular structure changes, and macroscopic reaction phenomena. This solves the problems that a single spectral component cannot simultaneously perform structural analysis and pressure calibration, and that a single imaging component cannot determine the nature of the reaction. The common optical path in this embodiment avoids repeated positioning errors of the sample micro-region by multiple optical paths, ensuring that infrared, Raman, imaging, and fluorescence signals all originate from the same reaction region. This solves the problem that micro-samples (≤1mg) cannot meet the requirements for separate detection by multiple optical paths, and achieves synchronous acquisition of multiple signals under micro-dose samples. This is a technical effect that cannot be achieved by a single component or non-integrated design. 2. Modular design of the common optical path enables high efficiency in micro-area detection. Compared to the design of independent optical paths for each component, the common optical path in this embodiment avoids repeated positioning errors of the sample micro-area by multiple optical paths, ensuring that infrared, Raman, imaging, and fluorescence signals all originate from the same reaction area, thus solving the problem that micro-samples (≤1mg) cannot meet the requirements of separate detection by multiple optical paths. 3. The closed-loop scheduling of the synchronous control module 7 enables the full capture of the dynamic process. When the pressure loading module applies microsecond-level dynamic pressure to the sample, each component can capture the entire process of the material from "structural change" to "macroscopic reaction" in the same time dimension, solving the problems of missed detection of reaction start time and mismatch between pressure and signal caused by asynchronous timing in traditional non-integrated designs.

[0024] In one specific embodiment, the pressure loading module includes a diamond anvil cell 102 for placing an energetic sample, a brake for dynamically loading and unloading pressure on the diamond anvil cell 102 during operation, and a pre-tightening component for initial alignment and static pre-tightening of the diamond anvil cell 102 before operation. It should be noted that the pre-tightening component is an independent fine-tuning pre-tightening screw; the distinction between before and during operation lies in whether power is applied to begin testing. The brake is electrically connected to a power amplifier 104, which is electrically connected to a function generator 105. The power amplifier 104 drives the actuator; the function generator 105 generates programmable drive waveforms (such as ramp waves and square waves) and can be activated by an external trigger signal.

[0025] Meanwhile, the pressure loading module also includes a bracket 101, which is a rigid, integrally formed bracket. A diamond anvil cell 102 is mounted on the bracket 101, and a brake is threadedly connected to the lower part of the bracket 101. The brake is a ring-shaped piezoelectric ceramic actuator 103. Specifically, the upper part of the bracket 101 has a precision groove for accommodating the diamond anvil cell 102, and the lower part has a threaded interface. The piezoelectric ceramic actuator 103 is a ring-shaped structure and is fixed to the lower part of the bracket 101 by a threaded connection. The axial displacement generated by the piezoelectric ceramic actuator 103 is used to apply dynamic pressure to the diamond anvil cell 102.

[0026] As a preferred embodiment, the piezoelectric ceramic actuator 103 has a ring-shaped hollow structure, allowing the light source to penetrate the hollow cavity of the piezoelectric ceramic from bottom to top and directly irradiate the sample on the diamond anvil cell 102. This avoids the problem of the actuator blocking the light path and ensures the accuracy of signal acquisition. The pressure loading module, through the setting of the pre-tightening element, avoids premature sample breakage or uneven force due to poor initial contact, ensuring uniform pressure application to small-dose samples. It also supports programmable waveform loading, enabling systematic study of sensitivity characteristics at different loading rates, and adapting to the testing needs of micro-samples of novel energetic materials.

[0027] In one specific embodiment, the common optical path module includes a first-stage multicolor beam splitter 201, a second-stage multicolor beam splitter 202, a third-stage multicolor beam splitter 203, and an objective lens 204 arranged sequentially along the same optical axis (also referred to as the common optical axis), with the objective lens 204 being close to the pressure loading module; the objective lens 204 is an integrated broadband adapter objective lens, closest to the sample, used for focusing the excitation light and collecting the signal light; the objective lens 204 is fixed by a three-dimensional electrically adjustable frame, and its focusing center is precisely aligned with the center of the sample cavity in the diamond anvil cell 102.

[0028] The first-stage multicolor beam splitter 201, the second-stage multicolor beam splitter 202, and the third-stage multicolor beam splitter 203 correspond to different wavelengths of light. Specifically, the first-stage multicolor beam splitter 201 is highly reflective of mid-infrared light, the second-stage multicolor beam splitter 202 is highly reflective of visible light, and the third-stage multicolor beam splitter 203 is highly reflective of a specific laser wavelength. Here, the third-stage multicolor beam splitter 203 is generally a single wavelength, with common wavelengths including 532nm, 875nm, and 1064nm, depending on the specific situation. The reflecting surfaces of the first-stage multicolor beam splitter 201, the second-stage multicolor beam splitter 202, and the third-stage multicolor beam splitter 203 are all at a 45° angle to the same optical axis, and the center of the same optical axis is coaxially and cofocally arranged with the center of the sample cavity of the diamond anvil cell. The entire common optical path is covered with a stainless steel light shield, lined with light-absorbing material to minimize stray light interference.

[0029] Meanwhile, the first-stage multicolor beam splitter 201, the second-stage multicolor beam splitter 202, and the third-stage multicolor beam splitter 203 respectively separate the corresponding optical paths into different functional components in the functional component module.

[0030] It is worth noting that since this application targets "≤1mg samples", 1mg samples only exist in submicron-level sample cavities. Conventional spectrophotometry does not require precise alignment of the micro-area and is prone to signal loss. This embodiment uses a three-stage beam splitter that is coaxial, confocal and at the same height as the sample cavity. The objective lens is finely adjusted to focus the micro-area through three-dimensional electric adjustment to achieve precise spectrophotometric acquisition of micro-samples.

[0031] Secondly, the reaction signal of trace samples is extremely weak, and conventional spectrophotometry does not have targeted stray light suppression, which can easily mask the effective signal. In this embodiment, an external stainless steel light shield and internal light-absorbing material are used in the optical path, combined with wavelength-specific spectrophotometry of the beam splitter to filter out stray light and improve the signal-to-noise ratio of weak signals.

[0032] Then, small-dose measurement requires spatiotemporal synchronization of multiple signals. Conventional spectral splitting only separates the optical paths and does not have a synchronous timing coordination design. This application couples the step-by-step spectral splitting with the synchronization control module 7, and unifies the triggering, delay compensation and timestamp binding to ensure that the multiple signals after spectral splitting are strictly synchronized with the dynamic pressure loading, so as to realize in-situ detection.

[0033] The common optical path module in this embodiment adopts a coaxial confocal structure with "three-stage multicolor beam splitter and integrated wideband adapter objective" through multispectral coaxial confocal design and anti-interference design. The optical axis is precisely aligned with the center of the sample cavity, and a light shield is set on the outside and light-absorbing material is lined inside. It is specially adapted to the synchronous transmission of multispectral signals (infrared / Raman / fluorescence / imaging) of samples ≤1mg, which solves the problem of high-precision signal coupling that cannot be achieved by existing technology.

[0034] In one specific embodiment, the functional component module includes an infrared spectroscopy measurement component, a Raman spectroscopy measurement component, a fluorescence spectroscopy measurement component, and a high-speed imaging component; In this process, the infrared spectroscopy measurement component emits infrared light to transmit and excite the energetic sample. The transmitted signal is collected by the objective lens 204 and transmitted to the first-stage multicolor beam splitter 201. The first-stage multicolor beam splitter 201 then reflects the light to the infrared detector 303 in the infrared spectroscopy measurement component. The optical path sequence is as follows: the infrared light emitted by the infrared light source 301 illuminates the sample from below. After the transmitted light carries the sample absorption information, it is collected by the objective lens 204 and reflected by the first-stage multicolor beam splitter 201 to the filtering unit 302, and finally received by the infrared detector 303.

[0035] Specifically, the infrared spectroscopy measurement component includes an infrared light source 301, a filtering unit 302, and an infrared detector 303; the infrared light source 301 is positioned on the transmission optical path side of the first-stage multicolor beam splitter 201. That is, the infrared light source 301 is placed at the end of the piezoelectric ceramic actuator 103 furthest from the diamond anvil cell 102, and its output optical axis is precisely collinear with the hollow axis of the piezoelectric ceramic actuator 103, the axis of the diamond anvil cell 102, and the main optical path of the system. Infrared light sequentially passes through the hollow piezoelectric ceramic actuator 103, the lower diamond, the sample cavity, and the upper diamond, completing transmission excitation. The transmitted infrared signal carrying sample absorption information is first collected and collimated by the integrated broadband adapter objective located above the sample, and then transmitted to the first-stage multicolor beam splitter 201. After being reflected by the first-stage multicolor beam splitter 201, the infrared signal light enters the filtering unit 302 and is finally received by the infrared detector 303.

[0036] The Raman spectroscopy measurement component emits a laser beam, which is reflected by the third-stage multicolor beam splitter 203 and enters the common optical path. The objective lens 204 focuses the laser beam to excite the sample. The generated Raman scattered light returns along the original path and passes sequentially through the first-stage multicolor beam splitter 201, the second-stage multicolor beam splitter 202, and the third-stage multicolor beam splitter 203. Finally, it is reflected by the Raman / fluorescence beam splitter 502 and enters the Raman spectroscopy detector 504 in the Raman spectroscopy measurement component.

[0037] Specifically, the Raman spectroscopy measurement assembly includes a pulsed laser 501, a Raman / fluorescence beam splitter 502, a Raman filter 503, and a Raman spectroscopy detector 504; and the pulsed laser 501 is disposed on the reflected light path side of the third-stage multicolor beam splitter 203.

[0038] The fluorescence spectroscopy measurement component emits a laser, and the generated fluorescence signal returns along the original path, passing sequentially through the first-stage multicolor beam splitter 201, the second-stage multicolor beam splitter 202, and the third-stage multicolor beam splitter 203, before being reflected by the Raman / fluorescence beam splitter 502 to the fluorescence detector 602 in the fluorescence spectroscopy measurement component; wherein the fluorescence spectroscopy measurement component and the Raman spectroscopy measurement component share the same laser source.

[0039] Specifically, the fluorescence spectroscopy measurement component includes a pulsed laser 501, a Raman / fluorescence beam splitter 502, a fluorescence filter 601, and a fluorescence detector 602; wherein the Raman spectroscopy measurement component and the fluorescence spectroscopy measurement component share the same pulsed laser 501 and Raman / fluorescence beam splitter 502.

[0040] In other words, for the Raman spectroscopy and fluorescence spectroscopy measurement components, the pulsed laser 501 (e.g., 532nm) is positioned on the reflected light path side of the third-stage multicolor beam splitter 203. The laser beam is reflected by the third-stage multicolor beam splitter 203 into the common light path, where it is focused by the objective lens 204 to excite the sample. The generated Raman scattered light and fluorescence signal return along the original path, passing sequentially through the first-stage multicolor beam splitter 201, the second-stage multicolor beam splitter 202, and the third-stage multicolor beam splitter 203, before being split by the Raman / fluorescence beam splitter 502. The reflected light, mainly Raman signals, is received by the Raman spectrometer detector 504 after passing through the Raman filter 503; the transmitted light, mainly fluorescence signals (including ruby ​​fluorescence), is received by the fluorescence detector 602 after passing through the fluorescence filter 601.

[0041] The high-speed imaging component is positioned on the reflected light path side of the second-stage multicolor beam splitter, directly acquiring the morphology and emission images of the energetic sample during pressure loading. The images are then reflected by the second-stage multicolor beam splitter and received by the high-speed camera within the high-speed imaging component. Specifically, the high-speed imaging component includes a filter and a high-speed camera, both positioned on the reflected light path side of the second-stage multicolor beam splitter. This allows natural light or the sample's own emission to illuminate the sample. The reflected light is collected by the objective lens 204, reflected by the second-stage multicolor beam splitter 202 to the filter 401, and then captured by the high-speed camera 402.

[0042] In this embodiment, the Raman spectroscopy and fluorescence spectroscopy components share the pulsed laser 501 as the excitation source, which is an optimized design based on detection requirements. This embodiment has fully considered the adverse consequences that may arise from sharing a light source and has effectively solved the problem through targeted optical path design and device configuration.

[0043] 1. Sharing a light source may have two adverse consequences: a. Fluorescence signal background interference. Due to the strong fluorescence signal and weak Raman signal, the sample's Raman signal may be overwhelmed by the fluorescence. Solution: In the collection optical path of the Raman / fluorescence spectroscopy component, a Raman / fluorescence beam splitter 502 is set. This beam splitter is designed based on the wavelength difference between Raman scattered light and fluorescence signal: it provides high reflection of Raman scattered light and high transmission of fluorescence signal.

[0044] 2. May cause signal crosstalk. Solution: Install Raman filter 503 in the Raman detection branch. This filter is a notch filter / long-pass filter, which can accurately filter out the elastic scattered light of the laser and the residual fluorescent background light; install fluorescence filter 601 in the fluorescence detection branch. This filter is a bandpass filter, which can accurately match the fluorescence emission wavelength of the ruby ​​pressure scale and the energetic material, and filter out the residual Raman scattered light and stray light.

[0045] Advantages of using a shared laser source: It avoids the excessive optical path complexity and micro-area positioning errors introduced by multiple laser sources, simplifies the coupling design of the common optical path, and ensures that the excitation light is accurately focused on the same micro-area of ​​the sample cavity; it can realize dual signal acquisition under a single excitation source, ensuring that the excitation timing of Raman and fluorescence signals is completely synchronized, and it is more conducive to accurately correlate molecular structure changes (Raman) with pressure calibration (fluorescence) through timestamps, thereby improving the synchronicity of sensitivity parameter determination.

[0046] In one specific embodiment, the synchronization control module 7 includes a high-precision timing controller and a multi-channel shielded cable. The multi-channel shielded cable sends timed trigger and clock signals to components in the pressure loading module, the common optical path module, and the functional component module to ensure the time synchronization of all actions and data acquisition.

[0047] In other words, the multi-channel shielded cable of the synchronization control module 7 sends precisely timed trigger and clock signals to the function generator 105 of the pressure loading module, the power amplifier 104, the infrared detector 303 of the infrared spectroscopy measurement component, the Raman spectroscopy detector 504 of the Raman spectroscopy measurement component, the fluorescence detector 602 of the fluorescence spectroscopy measurement component, and the high-speed camera 402 of the high-speed imaging component, ensuring that all actions and acquisitions are strictly synchronized.

[0048] like Figure 2 As shown, a method for testing the sensitivity of a milligram-to-sub-milligram energetic material using a system as described in any of the above embodiments includes the following steps: S1: The energetic sample to be tested and the ruby ​​pressure scale are loaded together into the sealed sample chamber in the pressure loading module; this includes first loading the trace energetic sample to be tested and the ruby ​​pressure scale together into the sealed sample chamber of the diamond anvil cell 102; placing the loaded diamond anvil cell 102 in the groove of the support 101, and performing preliminary alignment and fixation. S2: The pressure loading module is triggered by the synchronous control module 7 to apply controllable pressure to the sample; at the same time, the functional component module is triggered by the synchronous control module 7 to collect pressure signals, molecular structure signals and morphology image signals in real time during the pressure loading process; of course, before performing step S2, the initialization settings of each module are included, including setting the working parameters of each module. S3: Based on the acquired synchronous pressure signal, molecular structure signal, and morphology image signal, analyze and determine the sensitivity parameters of the energetic sample.

[0049] Specifically, step S3 includes: By fitting the displacement of the ruby ​​fluorescence peak, the pressure change curve in the sample chamber over time is inverted and recorded in real time to determine the pressure amplitude and loading rate of dynamic loading. By analyzing the changes in characteristic peaks of the infrared absorption spectrum and Raman spectrum of the sample during the dynamic process, the starting point and extent of chemical decomposition of energetic samples can be determined. By analyzing the sample morphology, color, or luminescence abrupt changes recorded by high-speed imaging, evidence can be obtained of the occurrence of chemical reactions. Using the synchronization timestamp, the critical pressure value P that triggers sample decomposition was determined. R and its corresponding instantaneous loading rate V; Using the formula S=P R The dynamic sensitivity factor S under this dynamic loading condition is calculated as a key indicator for quantitatively evaluating the impact sensitivity of energetic materials.

[0050] Of course, it is worth noting that this method can also be repeated at different loading rates by changing the output waveform of the function generator to obtain a series of critical pressure values ​​P that cause the material to react. R The instantaneous loading rate V is used to depict the dynamic sensitivity boundary of the material or determine its minimum sensitivity threshold.

[0051] In this embodiment, the method first initializes each light source and detector during measurement. Then, the synchronization control module 7 sends a main trigger signal, activating the function generator 105 and power amplifier 104 to drive the piezoelectric ceramic actuator 103 to dynamically load the sample. Simultaneously, it activates each spectral and imaging device according to a preset timing sequence for data acquisition. Using the synchronized timestamps, the measured pressure evolution, molecular structure changes (characteristic peaks of decomposition products), and macroscopic morphological abrupt changes (such as luminescence and vaporization) are correlated and analyzed. Finally, the critical pressure (P) that triggers the chemical reaction is determined. R The dynamic sensitivity factor (S) of the material is calculated from the loading rate (V) at that moment. Furthermore, the waveform, amplitude, and rate of dynamic loading can be flexibly edited through the function generator 105, thereby enabling a systematic study of the sensitivity characteristics of energetic materials under different pressure loading paths.

[0052] To facilitate a further understanding of this application, the following examples of embodiments are provided: A precision sampling tool was used to place a CL-20 sample of less than 1 mg along with several micron-sized ruby ​​particles into the sample chamber of a diamond anvil cell 102, sealing it to form a thin sheet. The diamond anvil cell was then installed into a support 101 and lightly secured with pre-tightening screws. The infrared light source 301, pulsed laser 501, and all detectors were turned on, and the detectors were preheated and initialized. The function generator 105 was set to output a fast ramp voltage waveform via computer software, and the acquisition parameters of each measuring device (such as spectral integration time and camera frame rate) were set.

[0053] Start-up test: The synchronous control module 7 sends out the main trigger pulse, the function generator 105 starts immediately, the power amplifier 104 drives the piezoelectric ceramic actuator 103 to extend rapidly, and applies a load with linearly increasing pressure to the sample; at the same time, the infrared detector 303, the high-speed camera 402, the Raman spectroscopy detector 504 and the fluorescence detector 602 start high-speed acquisition synchronously according to the preset delay.

[0054] Data processing and analysis: 1. Pressure calibration: Extract the ruby ​​R1 peak position from the data of fluorescence detector 602, calculate the pressure value in real time, obtain the pressure-time (Pt) curve, and calculate the loading rate V; 2. Structural analysis: The attenuation of the characteristic peaks of CL-20 and the appearance of possible newly formed decomposition product peaks were monitored from the data of Raman spectroscopy detector 504 and infrared detector 303. 3. Morphological observation: Observe whether the sample exhibits violent reaction phenomena such as luminescence, discoloration, bubbles, or plasma flashes from the high-speed camera 402 image sequence; 4. Correlation Determination: Using the synchronization timestamp, determine the moment t when the irreversible change in the Raman / infrared spectrum occurs. R And / or the moment when a flash occurs in a high-speed image. Find t on the Pt curve. R The corresponding critical pressure P R ; 5. Sensitivity calculation: According to the formula S=P R • V, calculate the dynamic sensitivity factor for this experiment. For example, if P is measured... R The instantaneous loading rate V at this point is approximately 50 GPa, and the instantaneous loading rate V is approximately 120 GPa / s. Therefore, S is calculated to be 6000 GPa² / s. 6. Threshold Determination: By changing the output waveform of the function generator (e.g., changing the ramp slope), the experiment is repeated at different loading rates to find a series of critical thresholds (P) that lead to material reaction. R The point (V) is used to depict the dynamic sensitivity boundary of the material or determine its minimum sensitivity threshold.

[0055] The examples described herein are merely preferred embodiments of the invention and are not intended to limit the concept and scope of the invention. Any modifications and improvements made by those skilled in the art to the technical solutions of the invention without departing from the design concept of the invention should fall within the protection scope of the invention.

Claims

1. A sensitivity testing system for milligram- to sub-milligram-level energetic materials, characterized in that: include: Pressure loading module: used to apply dynamic pressure to energetic samples; Common optical path module: used to collect light of at least two different wavelengths and separate the optical paths of different wavelengths into different functional components in the functional component module; Functional component module: used for in-situ observation of the structural evolution and reaction phenomena of energetic samples under pressure loading; Synchronization control module: Used to ensure the time synchronization of the pressure loading module, common optical path module and functional component module when they are working.

2. The sensitivity testing system for milligram-to-sub-milligram energetic materials according to claim 1, characterized in that: The pressure loading module includes a diamond anvil cell for placing an energetic sample, a brake for dynamically loading and unloading the diamond anvil cell during operation, and a pre-tightening element for initial alignment and static pre-tightening of the diamond anvil cell before operation; the brake is electrically connected to a power amplifier, and the power amplifier is electrically connected to a function generator.

3. The sensitivity testing system for milligram-to-sub-milligram energetic materials according to claim 2, characterized in that: It also includes a support, on which a diamond anvil is provided, and a brake is threadedly connected to the bottom of the support; and the brake is a piezoelectric ceramic actuator with a ring structure.

4. The sensitivity testing system for milligram-to-sub-milligram energetic materials according to claim 2, characterized in that: The common optical path module includes a first-stage multicolor beam splitter, a second-stage multicolor beam splitter, a third-stage multicolor beam splitter, and an objective lens arranged sequentially along the same optical axis, with the objective lens located close to the pressure loading module; The first-stage polychromatic beam splitter, the second-stage polychromatic beam splitter, and the third-stage polychromatic beam splitter each correspond to different wavelengths of light. Meanwhile, the first-stage multicolor beam splitter, the second-stage multicolor beam splitter, and the third-stage multicolor beam splitter each separate the corresponding optical path into different functional components in the functional component module.

5. The sensitivity testing system for milligram-to-sub-milligram energetic materials according to claim 4, characterized in that: The first-stage multicolor beam splitter is highly reflective of mid-infrared light, the second-stage multicolor beam splitter is highly reflective of visible light, and the third-stage multicolor beam splitter is highly reflective of specific laser wavelengths. Furthermore, the reflecting surfaces of the first-stage multicolor beam splitter, the second-stage multicolor beam splitter, and the third-stage multicolor beam splitter are all at a 45° angle to the same optical axis, and the center of the same optical axis is coaxially and cofocally set with the center of the sample cavity of the diamond anvil cell. The focusing center of the objective lens is aligned with the center of the sample chamber of the diamond anvil cell.

6. The sensitivity testing system for milligram-to-sub-milligram energetic materials according to claim 4, characterized in that: The functional component module includes an infrared spectroscopy measurement component, a Raman spectroscopy measurement component, a fluorescence spectroscopy measurement component, and a high-speed imaging component; The infrared spectroscopy measurement component emits infrared light to transmit and excite the energetic sample. The transmitted signal is collected by the objective lens and transmitted to the first-stage multicolor beam splitter, which then reflects the signal to the infrared detector in the infrared spectroscopy measurement component. The Raman spectroscopy measurement component emits a laser beam, which is reflected by the third-stage multicolor beam splitter and enters the common optical path. The laser beam is then focused by the objective lens to excite the sample. The generated Raman scattered light returns along the original path and passes through the first-stage multicolor beam splitter, the second-stage multicolor beam splitter, and the third-stage multicolor beam splitter in sequence. After being reflected by the Raman / fluorescence beam splitter, it is sent to the Raman spectroscopy detector in the Raman spectroscopy measurement component. The fluorescence spectroscopy measurement component emits a laser, and the resulting fluorescence signal returns along the original path, passing sequentially through the first-stage multicolor beam splitter, the second-stage multicolor beam splitter, and the third-stage multicolor beam splitter, before being reflected by the Raman / fluorescence beam splitter to the fluorescence detector in the fluorescence spectroscopy measurement component; wherein the fluorescence spectroscopy measurement component and the Raman spectroscopy measurement component share the same laser source. The high-speed imaging component is located on the reflected light path side of the second-stage multicolor beam splitter, directly acquiring the morphology and emission images of energetic samples during the pressure loading process. After being reflected by the second-stage multicolor beam splitter, the images are received by the high-speed camera in the high-speed imaging component.

7. The sensitivity testing system for milligram-to-sub-milligram energetic materials according to claim 6, characterized in that: The infrared spectroscopy measurement component includes an infrared light source, a filtering unit, and an infrared detector; and the infrared light source is located on the transmission optical path side of the first-stage multicolor beam splitter. The Raman spectroscopy measurement assembly includes a pulsed laser, a Raman / fluorescence beam splitter, a Raman filter, and a spectral detector; and the pulsed laser is positioned on the reflected light path side of the third-stage multicolor beam splitter. The fluorescence spectroscopy measurement component includes a pulsed laser, a Raman / fluorescence beam splitter, a fluorescence filter, and a fluorescence detector; wherein the Raman spectroscopy measurement component and the fluorescence spectroscopy measurement component share the same pulsed laser and Raman / fluorescence beam splitter. The high-speed imaging component includes a filter and a high-speed camera, both of which are located on the reflected light path side of the second-stage multicolor beam splitter.

8. A sensitivity testing system for milligram-to-sub-milligram energetic materials according to claim 1 or 7, characterized in that: The synchronization control module includes a timing controller and a multi-channel shielded cable. The multi-channel shielded cable sends timed trigger and clock signals to components in the pressure loading module, common optical path module, and functional component module to ensure the time synchronization of all actions and data acquisition.

9. A method for using a sensitivity testing system for milligram- to sub-milligram-level energetic materials as described in any one of claims 1-8, characterized in that: Includes the following steps: S1: The energetic sample to be tested and the ruby ​​pressure gauge are loaded together in the sealed sample chamber of the pressure loading module; S2: The synchronous control module triggers the pressure loading module to apply controllable pressure to the sample; at the same time, the synchronous control module triggers the functional component module to collect pressure signals, molecular structure signals and morphology image signals in real time during the pressure loading process. S3: Based on the acquired synchronous pressure signal, molecular structure signal, and morphology image signal, analyze and determine the sensitivity parameters of the energetic sample.

10. The method for using a sensitivity testing system for milligram- to sub-milligram-level energetic materials as described in any one of claims 1-8, as claimed in claim 9, characterized in that: Step S3 specifically includes: By fitting the displacement of the ruby ​​fluorescence peak, the pressure change curve in the sample chamber over time is inverted and recorded in real time to determine the pressure amplitude and loading rate of dynamic loading. By analyzing the changes in characteristic peaks of the infrared absorption spectrum and Raman spectrum of the sample during the dynamic process, the starting point and extent of chemical decomposition of energetic samples can be determined. By analyzing the sample morphology, color, or luminescence abrupt changes recorded by high-speed imaging, evidence can be obtained of the occurrence of chemical reactions. Using the synchronization timestamp, the critical pressure value P that triggers sample decomposition was determined. R and its corresponding instantaneous loading rate V; Using the formula S=P R The dynamic sensitivity factor S under this dynamic loading condition is calculated as a key indicator for quantitatively evaluating the impact sensitivity of energetic materials.

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